1. Field of the Invention
The present invention relates to truck restraints
2. Description of the Prior Art
Truck restraints are used to maintain a trailer in position against a loading dock while it is being loaded or unloaded. Inadvertent movement of the trailer would produce a hazardous situation for the vehicle performing the loading or unloading and therefore it is necessary to ensure that the trailer is maintained in position.
A variety of truck restraints have been purposed including chocks that are positioned automatically in front of the trailer wheels to maintain the vehicle in position. A more common type of restraint utilises a hook secured to the loading dock area and which is elevated to engage the ICC bar provided on trailers. The hook is elevated from a stored position to an engaged position and thus engages the ICC bar to inhibit relative horizontal movement between the dock and the trailer.
U.S. Pat. No. 4,759,678 to Hagemen discloses a truck restraint in which a carriage is mounted on tracks and moved vertically along the tracks by a hydraulic actuator. A hook is carried by the carriage and moved into engagement with the ICC bar as the carriage is moved from its stored to its operative position. In the Hagemen patent, the actuator is mounted vertically but alternative configurations of actuator are shown in U.S. Pat. No. 4,830,563 to Yeakle. In the Yeakle patent, the actuator is inclined to the vertical to allow the restraint to adopt a lower profile whilst still inducing vertical movement of the carriage along the guide tracks. Similar arrangements are shown in U.S. Pat. No. 5,297,921 to Springer and U.S. Pat. No. 4,938,647 to Erlandsson. In each of the above arrangement, the carriage and hook assembly are fixed to the tracks that guide the vertical movement and as such extend upwardly from the dock floor by the extent of the hook. It is not unusual for the dock to be formed at the bottom of an inclined ramp so that the loading dock may be maintained at the floor level of the building of which the loading dock is part, As such, it is desirable that the truck restraint has a minimal profile to avoid interference between the restraint and the ICC bar as the trailer is being positioned against the dock. In each of the above references, the minimum profile is that presented by the height of the carriage and hook and in certain conditions this does result in interference.
It is therefore an object of the present invention to obviate or mitigate the above disadvantages.